Labyrinth packing



Oct. 11, 1932. o. A. WIBERG 1,882,267

LABYRINTH PACKING Filed April 7, 1930 Fatented Oct. 11, 1932 UNrrEnstares srwar caries Y OSCAR .em'ronwrnnne, on rrnsrone, swnnnnApplication and April 7, 1930, Serial No. 442,302, and in Sweden April8, 1929.

This invention relates to labyrinth pack,- ings of the type whichcomprises annular disks having sleeve-shaped projections on their sidesfacingeach other, the sleeveshaped projections of one such disk engagingthe spaces between the projections of the adjacent disk or disks. Inorder to prevent theprojections of the disks of such packingsfromtouching each other due to'such variations of size as are caused bythe varying temperatures to which the projections may be subjected theremust-be both axial clearance between the disks andradial clearance vbetween the sleeve-shaped projections of the disks. The axial clearanceis taken care of ularly those of larger dimensions,fwhich aredesignedfor high pressures there is a tendency, however, for the projections tochange their diameter outwards or inwards in a greater degree than thatcorresponding to the variations of the temperature, and, moreover, thereis a tendency for the disks to bend. This is due to the fact that,according to the direction of flow of the medium, a higher or lowerpressure will appear on the one side or the other of the projections ordisks.

The object of the invention isto overcome said difiiculty in orderthereby to permit the use of a smaller radial clearance with a resultinghigher sealing effect of the packing and a reduced tendency of touching.

The invention is characterized, chiefly, by the fact that thesleeve-shaped projections are strengthened at their base portionswhereby they are rendered more rigid and less sensible to externalpowers.

In the accompanying drawing one embodiment of the invention isillustrated. v

Figure 1 is an axial section of a shaft between the shaft 1 and the wall2 packing constructed according to the vention.

Figs. 2 and-3 are axial sections on an enlarged scale of parts of twopacking disks shownin two different positions.

With reference'toFig. 1, the numeral indicates a shaft and 2 is a wallthrough which the shaft 1 shall extend tightly. On the one side of thewall 2 (as to the right thereof) atmospheric pressure exists, and on theother side of the wall 2 (as to the left thereof) there exists a higherpressure, as, for instance, a steam pressure. In order to preventleakage of the high pressure medium a labyrinth packing is inserted in.an opening formed in the wall 2 andin a ring 3 bolted tothe wall 2.

The labyrinth packing comprises a series of annular disks 4, 5, 6,, 7.secured to the shaft 1, the parts of which nearest to the shaft areshaped as distance pieces, and an other series of similar disks 8, 9, 10secured to the ring 3 and the wall2, respectively, and projecting intothe spaces'between the disks 4, 5, 6, 7. Formed on'the sides of thedisks facing each other are axiallyextendlng, sleeve-shaped concentricprojections 11 which are caused in the assembling of the "packing toengage between eachother. Said '80 projections may be formed integrallywith the respective disks or secured thereto in any appropriate way.

As will more readily appear from Figs. 2 and 3, the projections 11 arecut ofi coni- .85 cally at their outer edges and formed with inwardlydirected, similarly conical flanges 12. In this packing the axialclearance is determined by the axialextent to which the projections 11of each of two adjacent disks may enter the spaces between theprojections of the other disk. Fig. 2 shows a position whichpresents agreat clearance, and Fig. 3

shows the position after maximal displa'cement of the disks, that is tosay, with'the 0 projections 11 of each disk in contactwith the oppositedisk, in which position there is no axial clearance at all. The radial,

clearanceis determined by the distance be-w their base,

tween the sealing edges 12 and the adjacent inner projection 11. I

The projections 11, the hitherto used section of which is represented bythe area 13-14-15-.1613 in Fig. 2, are formed according to thisinvention with a swell at represented by the area 13,16-

1718-13 in'Fig. 2, which swell is located on the same side as therespective seallng flange 12, that is on the inner side of theprojection. This swell w1ll' thus form an annular strengthening ribwhich adds essentially to the resistance of the pro ections to externalpowers. 3 p j The dimensions of said strengthening ribs are so chosenthat inthe position shown 1n Fig. 3, that is to say, with the seal ngflanges 12 ofeach disk in engagement wlth the adjacent disk,contactexists between each point 17 of the strengthening rib and the edge 15 ofthe adjacentprojectionll, as shown in Fig. 3. The area 16 -17 of thestrengthening rib represents a conical surface which in the positionshown in Fig. 3 forms an extension ofthe conical end surface of theadjacent projection 11. This will maintain the radial clearance constantirrespective of the relative axial position of the dlsks. his to benoted that the invention may be applied to all types of labyrinth pack--ings, whether.or not they are self-balanc ng and I formed integrallywith the respective disks.

What I claim is: I i 1. A labyrinth packmg,compr1s1ng annular diskswhich form axial spaces between I themselves and are movableaxiallytoward and from each other, sleeve-shaped projections on saiddisks extending axially into said spaces so as to overlap alternatelyfrom opposite sides, annular ribs at the base portion'of the, projectionson one side thereof, an-

nularsealing flanges at the free ends of the projections so located asto provide'-.sealing constrlctlons on the same side of the projectionsas the respective ribs, the radial thickness of the base portion of theprojections ineluding said rib being. equal to the radial space betweenadjacent projections of the same disk at the bases of the projections 2.A labyrinth packing, comprising annular disks which; form axial spacesbetween.

themselves and are movable axially. toward and from each other, sleeveshaped projections onjsaid disks axially extending into said spaces soasto overlap alternately from opposite sides, annular ribs at the baseportion of the projections on the inner circumferential surface thereof,and sealing flanges at the free ends of the projections 'so located asto provide sealing constrictionson the inner side a of the projections,the radial thickness of the baseportion of the projectionsincluding'said whether or not the pro ections are In testi on'ycylindrical outer surfaces and having their ends cut ofl along conicalsurfaces, the apices of which are directed away from the respectivedisks, inwardly directed similarly conical sealing flanges at said endsof the projections, annular strengthening ribs on the inner sideoftheprojections at the base there of, said strengthening ribs beingbounded in axial direction by conicalsurface which in that relative-iposition of the dis'ksin which the axial distance therebetween isshortest are each located on the same conical surface as the conical endsurface of the adjacent inner projection. c g

a 4. A labyrinth packing, comprising annularndisks which form axialspaces between themselves and are movable toward and from each otheraxially, sleeve-shaped concentric projections axially extending into.saidspaces alternately from the respective disks so as to overlapalternatelyfrom opposite sides, said sleeve-shaped projections havingstraight cylindrical outer surfaces and'having their ends cut offalongconical surfaces the apices of which are directed away from therespec tive disks, inwardly directed similarly conical sealing flangesat the ends of the projections, annular strengthening ribs on the innerside of the projections. at the base thereof, said strengthening ribsbeing bounded in axial di rection by conical surfaces which in thatrelative position ofthe disks in'which the axial distance therebetweenis shortest are each locatedon the same conical surface as the conicalend surface of the adj acent'inner pro-v jection, the radial thicknessof thebase portion of the projections being substantially equal to theradial space between adjacent projections of the same disk at the bases"of the projections so that in the saidrelative f opposite disk to .formthrottling places at thesetwo edges. I i p 7.

, whereof, I have signed my foscxn ANTON WIBERG] "name.

rib being equal to the radial space between ad- I

